Field of the Invention
The present invention relates to a transparent solid detergent superior in preservation stability and usability.
Discussion of the Background
Conventionally, as transparent solid detergent, those containing a higher fatty acid salt as a main agent and added with glycerin, sucrose, sorbitol or the like as a transparentizing agent are mainly used. Transparent solid detergent gives a sense of high quality and has high commercial value. However, a transparent solid detergent containing a higher fatty acid salt as a main agent lacks transparency and has defects such as irritation to the skin, poor foaming property in hard water and the like. Thus, transparent solid detergents using acyl acidic amino acids have been studied.
For example, a transparent solid detergent containing N-long chain acyl acidic amino acid salt as a main agent is known to be superior in transparency and mild to the skin; however, it is insufficient in terms of high temperature stability and foaming (patent document 1).
In addition, a transparent solid detergent using a salt of N-long chain acyl acidic amino acid salt in combination with ethanolamine salt and alkali metal salt has problems in that coloration occurs due to heating during production and in terms of adhesion of soft formulation to containers (patent document 2).
Furthermore, a transparent solid detergent in consideration of a molar composition ratio of potassium salt, sodium salt and ethanolamine salt of N-long chain acyl acidic amino acid salt has a problem in that it becomes soft in a high temperature and high humidity environment (patent document 3).
In addition, a transparent solid detergent wherein an N-long chain acyl acidic amino acid salt is blended with an alkyl-modified silicone as components is insufficient in terms of stability at low temperature and usability such as foaming power and easy rising off (patent document 4).
On the other hand, while a cleansing composition wherein acyl acidic amino acid and acyl neutral amino acid are blended in combination is known, it does not relate to a transparent solid detergent (patent document 5), and no case is known to date in which these two kinds of N-acyl amino acid salts were combined and studied in an attempt to solve the above-mentioned problem relating to transparent solid cleansing compositions.